The detection of autoantibodies in the liver diseases PBC, PSC and CAH may serve as a diagnostic in assessing the severity and/or progression of disease. For phase I of this proposal ARI plan to develop enzyme based immunoassays (EIAs) for the detection of autoantibodies associated with PBC. ARI plan to use the recombinantly engineered molecule "PDC-E2/BCOADH-E2" which contains the antigenic determinants for the two classes of autoantibodies associated with PBC as the detection antigen. Initially, ARI will generate a plate based EIA offering both positive and negative controls for comparison. Upon successful completion of this task, ARI using the designer molecule, will develop a hand-held diagnostic for detecting the autoantibodies associated with PBC. The hand-held EIA, will be a quick, simple system which could be performed in the hospital at the patient's bedside or in a physician's office. The data from the successful completion of this task would then serve as the technical base for the development of hand held EIA for the detection of autoantibodies associated with PSC/and CAH, as well as other autoimmune disorders.